Not long ago, the words "transvaginal ultrasound" were unlikely to be mentioned outside of a medical clinic. The procedure involves inserting into the vagina an exploratory probe, which uses sound waves to produce an image on a computer screen. Issues which might necessitate the examination include internal pathologies, fertility concerns, and troubled pregnancies. It is an important diagnostic tool that helps innumerable women every day.

The war over legalized abortion has been fought in many places, from courtrooms to capitol buildings, and billboards to street rallies. Metaphorically, it's always been waged in women's bodies. But new legislation weaponizing the transvaginal ultrasound wand help wage the war there quite literally.

Is it possible to imagine a more wrenching decision than whether or not to terminate an unborn child? Though the course of American culture often seems to be on a fixed and perpetual descent, the notion of the "casual abortion" is a myth. And yet representatives seem prepared to think the very least of their constituents, and determined to enforce the kind of state-sponsored shaming unseen since 17th-century New England. To be sure, ultrasounds are often administered before abortions are performed. But a physician makes that call. It is, after all, a medical decision. These mandates from the state have no relation to the patient's well-being. Just the opposite, in fact. They are about inflicting guilt when a woman is most vulnerable.

The velocity with which these laws now seem to meteor down from state houses suggest a malevolent recklessness by lawmakers. When these men are confronted, their often audacious responses defy comment. To vilify Tom Corbett, governor of Pennsylvania, is to do him a service. Villainy, at least, suggests thought. His favored bill (now moribund, it seems) actually compels doctors by law to point the ultrasound monitor at the patient. When asked by a reporter about the sadistic requirement, his grinning suggestion to women: "You just have to close your eyes."

Such was the environment when Jen Deaderick decided to fix things. Or rather, to mobilize women to fix things, using a power they already have. "The simplest thing for women to do isn't to march, or boycott," she said. "It's to vote. To use their hard-fought right to make change."

Deaderick, a writer living in Cambridge, Massachusetts, is founder of the #UseThe19th campaign. It encourages women to take advantage of the 19th Amendment to the Constitution, which guarantees women's suffrage. She enlisted help from journalists Dahlia Lithwick, Lizzie Skurnick, and Rebecca Traister, and the group introduced #UseThe19th to Twitter on March 1, to mark the beginning of Women's History Month.

The idea is simple. When posting news of particularly discouraging legislation to Twitter, append #UseThe19th to the back of it as a way of reminding women that such laws and such politicians are not permanent, and that women themselves are the vehicle for change. "I wanted something that would remind women to vote, and also evoke our history of activism," said Deaderick. "And I wanted it to be easy, and visual. So, that's why it's a hashtag."

The campaign quickly took flight, but went stratospheric when author Susan Orlean joined in. ("She blew the lid off the place.") Not long after, comedian Lizz Winstead, author Alice Bradley, and actress Martha Plimpton were on board. Vast swaths of Twitter embraced the tag and the idea, and now use it as a mechanism to unify, organize, and exchange their thoughts on issues of the day.

Presently, reproductive rights are the movement's top concern. As Deaderick explained: "We choose to have children, or we choose not to have children. We want to have children, but find we can't. We don't want to have children, but find ourselves pregnant anyway." Then the issue magnifies. "We have children, and struggle to feed them, and house them, and raise them well. Something that is so prominent in the lives of half the population cannot be considered a secondary issue."

Deaderick takes inspiration in Occupy Wall Street and its use of the #Occupy hashtag. "The Occupy movement was, and continues to be, masterful in their use of social media. They chose the perfect word. It's so evocative. You can both occupy a country, and a place in someone's heart. And I love that the Occupy movement drew on the flash mob phenomenon to rally people to physically gather at a particular spot," she said. "Like the Occupy movement, the #UseThe19th campaign asks people to change their physical location on Election Day. The intention behind #UseThe19th is to get women to occupy voting booths."

What started as a meme is now a movement. #UseThe19th has beachheads on all the major social networking sites, and plans to have large presences at the Unite Against the War on Women marches and rallies scheduled across the country on April 28. (Deaderick will be speaking at the rally in Boston, on City Hall Plaza.) The campaign intends to expand its focus to encouraging local democratic activity: canvassing for candidates, attending conventions, and running for office. Alice Paul, one of the suffragists responsible for the 19th Amendment, once famously said, "When you put your hand to the plow, you can't put it down until you get to the end of the row." Deaderick adds: "We're not at the end of the row yet."

It is somehow fitting that a New Englander is leading this charge against using shame and guilt as a method of governance. As another Bay Stater once wrote hopefully of the same problem, "at some brighter period, when the world should have grown ripe for it, in Heaven's own time, a new truth would be revealed, in order to establish the whole relation between man and woman on surer ground of mutual happiness."

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David W. Brown is a writer based in Baton Rouge, Louisiana. He is the author of One Inch From Earth, and his site is dwb.io.